I think 32mm is for old counterbearing. With new maingear and pinion, lenght of counterbearing is increased. I measured my motors (HKII-4225-500KV) shaft and it is 34mm. It fits perfect on counterbearing.

No shims. Maybe I measured wrong. But counterbearing design changed due to thicker main gear and pinion. I looked at your pictures and my motor shaft is a little out of counterbearing, it is not like yours. So probably you are right.

I could buy this kind of new Pyro 700-52LS motor in good price for my LOGO 600sx, but lot of people suggest Pyro 700-45LS in 12s setup....

Thanx,
Laci

There are some threads on this forum that people have gear stripping with this combo. I will suggest 12T with 700-45 motor. Main gear has more contact with this pinion. With lower KV, you will have less headspeed, but you don't need high headspeeds with a Logo.

Incorrect Meshing is what causes gear to strip. Never had a gear strip on my 11t pyro 52 jive Gov logos.
You should be able to run a 200 gsm paper between the gears without ripping. It is in the Mikado logo 600 3D manual.
With the SX 14mm main gear and pinion, it will be much harder to strip gears.